Just bought a CPO 06 X3 3.0i / 30k miles...."absolutely loving it" is an understatement.

However, with the windows down, I notice a very short "hiss" sound when hitting bumps coming from the suspension. I have only owned smaller sedans before...is this normal for a larger vehicle? It was a one-owner vehicle, so i assume it has recently passed the CPO inspection....making me believe that it isn't anything major.

Thanks in advance